Evaluation of cartilage repair tissue after matrix-associated autologous chondrocyte transplantation using a hyaluronic-based or a collagen-based scaffold with morphological MOCART scoring and biochemical T2 mapping: preliminary results

In cartilage repair, bioregenerative approaches using tissue engineering techniques have tried to achieve a close resemblance to hyaline cartilage, which might be visualized using advanced magnetic resonance imaging.

Quantitative T2 mapping of knee cartilage: differentiation of healthy control cartilage and cartilage repair tissue in the knee with unloading - initial results

Purpose: To prospectively determine on T2 cartilage maps the effect of unloading during a clinical magnetic resonance (MR) examination in the postoperative follow-up of patients after matrix-associated autologous chondrocyte transplantation (MACT) of the knee joint. Materials and Methods: Ethical approval for this study was provided by the local ethics commission, and written informed consent was obtained. Thirty patients (mean age, 35.4 years +/- 10.5) with a mean postoperative follow-up period of 29.1 months +/- 24.4 were enrolled. A multiecho spin-echo T2-weighted sequence was performed at the beginning (early unloading) and end (late unloading) of the MR examination, with an interval of 45 minutes. Mean and zonal region of interest T2 measurements were obtained in control cartilage and cartilage repair tissue. Statistical analysis of variance was performed. Results: The change in T2 values of control cartilage (early unloading, 50.2 msec +/- 8.4; late unloading, 51.3 msec +/- 8.5) was less pronounced than the change in T2 values of cartilage repair tissue (early unloading, 51.8 msec +/- 11.7; late unloading, 56.1 msec +/- 14.4) (P = .024). The difference between control cartilage and cartilage repair tissue was not significant for early unloading (P = .314) but was significant for late unloading (P = .036). Zonal T2 measurements revealed a higher dependency on unloading for the superficial cartilage layer. Conclusion: Our results suggest that T2 relaxation can be used to assess early and late unloading values of articular cartilage in a clinical setting and that the time point of the quantitative T2 measurement affects the differentiation between native and abnormal articular cartilage. (c) RSNA, 2010.

Material properties of common suture materials in orthopaedic surgery

Suture materials in orthopaedic surgery are used for closure of wounds, repair of fascia, muscles, tendons, ligaments, joint capsules, and cerclage or tension band of certain fractures. The purpose of this study was to compare the biomechanical properties of eleven commonly used sutures in orthopaedic surgery. Three types of braided non-absorbable and one type of braided absorbable suture material with different calibers (n=77) underwent biomechanical testing for maximum load to failure, strain, and stiffness. All samples were tied by one surgeon with a single SMC (Seoul Medical Center) knot and three square knots. The maximum load to failure and strain were highest for #5 FiberWire and lowest for #0 Ethibond Excel (p<0.001). The stiffness was highest for #5 FiberWire and lowest for #2-0 Vicryl (p<0.001). In all samples, the failure of the suture material occurred at the knot There was no slippage of the knot in any of the samples tested. This data will assist the orthopaedic surgeon in selection and application of appropriate suture materials and calibers to specific tasks.

Repair of ruptured abdominal aortic aneurysm in octogenarians

To determine whether advanced age was independently associated with prohibitive surgical risks or impaired long-term prognosis after ruptured aortic aneurysm repair.

Intratumoral budding as a potential parameter of tumor progression in mismatch repair-proficient and mismatch repair-deficient colorectal cancer patients

In colorectal cancer, tumor budding at the invasive front (peritumoral budding) is an established prognostic parameter and decreased in mismatch repair-deficient tumors. In contrast, the clinical relevance of tumor budding within the tumor center (intratumoral budding) is not yet known. The aim of the study was to determine the correlation of intratumoral budding with peritumoral budding and mismatch repair status and the prognostic impact of intratumoral budding using 2 independent patient cohorts. Following pancytokeratin staining of whole-tissue sections and multiple-punch tissue microarrays, 2 independent cohorts (group 1: n = 289; group 2: n = 222) with known mismatch repair status were investigated for intratumoral budding and peritumoral budding. In group 1, intratumoral budding was strongly correlated to peritumoral budding (r = 0.64; P < .001) and less frequent in mismatch repair-deficient versus mismatch repair-proficient cases (P = .177). Sensitivity and specificity for lymph node positivity were 72.7% and 72.1%. In mismatch repair-proficient cancers, high-grade intratumoral budding was associated with right-sided location (P = .024), advanced T stage (P = .001) and N stage pN (P < .001), vascular invasion (P = .041), infiltrating tumor margin (P = .003), and shorter survival time (P = .014). In mismatch repair-deficient cancers, high intratumoral budding was linked to higher tumor grade (P = .004), vascular invasion (P = .009), infiltrating tumor margin (P = .005), and more unfavorable survival time (P = .09). These associations were confirmed in group 2. High-grade intratumoral budding was a poor prognostic factor in univariate (P < .001) and multivariable analyses (P = .019) adjusting for T stage, N stage distant metastasis, and adjuvant therapy. These preliminary results on 511 patients show that intratumoral budding is an independent prognostic factor, supporting the future investigation of intratumoral budding in larger series of both preoperative and postoperative rectal and colon cancer specimens.

Mortality and neurologic injury after surgical repair with hypothermic circulatory arrest in acute and chronic proximal thoracic aortic pathology: effect of age on outcome

The goal of this study was to determine whether advanced age affects mortality and incidence of neurological injury in patients undergoing surgical repair with hypothermic circulatory arrest in acute and chronic thoracic aortic pathology.

Advanced nail surgery

Six techniques not yet widely known or used in the dermatologic surgery of the nails are briefly described. Small-to-medium-sized tumours of the proximal nail fold (PNF) can be excised and the defect repaired with advancement or rotation flaps. A superficial biopsy technique of the matrix for the diagnosis of longitudinal brown streaks in the nail, which allows rapid histological diagnosis of the melanocyte focus to be performed, is described here. Because the excision is very shallow and leaves the morphogenetic connective tissue of the matrix intact, the defect heals without scarring. Laterally positioned nail tumours can be excised in the manner of a wide lateral longitudinal nail biopsy. The defect repair is performed with a bipedicled flap from the lateral aspect of the distal phalanx. Malignant tumours of the nail organ often require its complete ablation. These defects can be covered by a full-thickness skin graft, reversed dermal graft, or cross-finger flap. The surgical correction of a split nail is often difficult. The cicatricial tissue of the matrix and PNF have to be excised and the re-attachment of these wounds prevented. The matrix defect has to be excised and sutured or covered with a free matrix graft taken either from the neighbouring area or from the big toe nail.

Three Strategies for Promoting Intellectual Engagement in Advanced Undergraduate Seminars

With the humanities increasingly contested, we must adopt pedagogical approaches that promote the integral role of humanistic inquiry in student academic achievement. Whether they explore the eighteenth-century novel, cultural artifacts of the Third Republic, or sociopolitical controversies in contemporary literature, the three models described in this article propose innovative learning strategies for advanced undergraduate French and Francophone Studies seminars that fulfill the humanistic goals of the American university. From directed close reading exercises to analysis of the historical archive to creative exploratory writing, these activities engage students intellectually with complex cultural and narrative materials from diverse traditions and periods.

Interaction of fine particles and nanoparticles with red blood cells visualized with advanced microscopic techniques

So far, little is known about the interaction of nanoparticles with lung cells, the entering of nanoparticles, and their transport through the blood stream to other organs. The entering and localization of different nanoparticles consisting of differing materials and of different charges were studied in human red blood cells. As these cells do not have any phagocytic receptors on their surface, and no actinmyosin system, we chose them as a model for nonphagocytic cells to study how nanoparticles penetrate cell membranes. We combined different microscopic techniques to visualize fine and nanoparticles in red blood cells: (I) fluorescent particles were analyzed by laser scanning microscopy combined with digital image restoration, (II) gold particles were analyzed by conventional transmission electron microscopy and energy filtering transmission electron microscopy, and (III) titanium dioxide particles were analyzed by energy filtering transmission electron microscopy. By using these differing microscopic techniques we were able to visualize and detect particles < or = 0.2 microm and nanoparticles in red blood cells. We found that the surface charge and the material of the particles did not influence their entering. These results suggest that particles may penetrate the red blood cell membrane by a still unknown mechanism different from phagocytosis and endocytosis.

Quality of analgesic treatment in patients with advanced prostate cancer: do we do a better job now? The Swiss Group for Clinical Cancer Research (SAKK) experience

GOALS OF WORK: The aim of this study was to evaluate pain intensity and the application of the WHO guidelines for cancer pain treatment in patients with prostate cancer treated at Swiss cancer centers. MATERIALS AND METHODS: We analyzed a series of five multicenter phase II clinical trials which examined the palliative effect of different chemotherapies in patients with advanced hormone-refractory prostate carcinoma. Of 170 patients, 1,018 visits were evaluable for our purpose, including ratings of pain intensity by patients and prescribed analgesics. MAIN RESULTS: No or mild pain was indicated by patients in 36 to 55% of the visits, more than mild pain in 30 to 46%. In 21% of the visits, the WHO pain treatment criteria (treatment according to one of the three steps; oral, rectal or transdermal application of the main dose; administration on a regular schedule) were fulfilled, and the Cleeland index was positive according to all recommendations. In 6% of the visits, neither the WHO criteria were fulfilled nor was the Cleeland index positive. This indicates insufficient pain treatment not following the WHO guidelines and that the prescribed analgesics were not sufficiently potent for the rated pain intensity. CONCLUSIONS: In this selective Swiss sample, the standard of analgesic treatment is high. However, there is still scope for improvement. This cannot solely be solved by improving the knowledge of the physicians. Programs to change the patients' attitude towards cancer pain, training to improve the physicians' communication skills, and institutional changes may be promising strategies.

MRI follow-up of TNF-dependent differential progression of atherosclerotic wall-thickening in mouse aortic arch from early to advanced stages

OBJECTIVES: An optimized, longitudinal in vivo magnetic resonance vessel wall-imaging protocol was evaluated regarding its capability of detecting differences in the time-dependent atherosclerotic lesion progression in the aortic arch between ApoE(-/-) and double-deficient ApoE(-/-)/TNF(-/-) mice at comparatively early plaque development stages. MATERIALS AND METHODS: Seven ApoE(-/-) and seven ApoE(-/-)/TNF(-/-) female mice underwent MRI at 11.75 teslas at four stages up to 26 weeks of age. A double-gated spin-echo MRI sequence was used with careful perpendicular slice positioning to visualize the vessel wall of the ascending aortic arch. RESULTS: Wall-thickness progression measured with MRI was significant at 11 weeks of age in ApoE(-/-) mice, but only at 26 weeks in ApoE(-/-)/TNF(-/-) mice. A significant correlation was found between MRI wall-thickness and lesion area determined on histology. CONCLUSION: MRI was shown to be sensitive enough to reveal subtle genetically-induced differences in lesion progression at ages earlier than 25 weeks.

Internal iliac artery embolization before endovascular repair of aortoiliac aneurysms with a nitinol vascular occlusion plug

PURPOSE: To evaluate the acute and midterm effectiveness of a novel vascular occlusion device for embolization of the internal iliac artery (IIA) before endovascular repair of aortoiliac aneurysms. MATERIALS AND METHODS: Between March 2005 and April 2006, nine men (mean age, 75 years +/- 5; range, 66-83 y) with aortoiliac aneurysms underwent bifurcated endovascular stent-graft procedures. All these patients were referred specifically for embolization. Pre- and perioperatively, eight patients underwent unilateral embolization and one underwent bilateral embolization of the IIA to prevent type II endoleak. Via a contralateral femoral approach with a 6-F or 8-F sheath, the embolization procedure was performed with an Amplatzer Vascular Plug, a self-expandable cylindrical device consisting of a nitinol-based wire mesh. Technical success, clinical outcome, and complications were evaluated. Follow-up at 3, 6, and 12 months was performed with clinical and radiologic examinations. RESULTS: IIA embolization was technically successful in all cases and no procedure-related complications occurred. Imaging at discharge and at 3-, 6-, or 12-month follow-up was accomplished in all nine patients. Control computed tomography and magnetic resonance angiography did not reveal retrograde perfusion of the aneurysmal sac, ie, type II endoleak. Three of nine patients (33.3%) reported symptoms of buttock claudication that did not resolve completely. Clinical symptoms such as bowel ischemia or sexual dysfunction were not observed. CONCLUSIONS: The midterm results of this study suggest that preoperative IIA embolization with a nitinol vascular occlusion plug during endovascular treatment of aortoiliac aneurysms is safe and effective.

Matched-pair analysis of endovascular versus open surgical repair of abdominal aortic aneurysms in young patients at low risk

PURPOSE: To compare clinical outcomes of endovascular and open aortic repair of abdominal aortic aneurysms (AAAs) in young patients at low risk. It was hypothesized that endovascular aneurysm repair (EVAR) compares favorably with open aneurysm repair (OAR) in these patients. MATERIALS AND METHODS: Twenty-five patients aged 65 years or younger with a low perioperative surgical risk profile underwent EVAR at a single institution between April 1994 and May 2007 (23 men; mean age, 62 years+/-2.8). A sex- and risk-matched control group of 25 consecutive patients aged 65 years or younger who underwent OAR was used as a control group (23 men; mean age, 59 years+/-3.9). Patient outcomes and complications were classified according to Society of Vascular Surgery/International Society for Cardiovascular Surgery reporting standards. RESULTS: Mean follow-up times were 7.1 years+/-3.2 after EVAR and 5.9 years+/-1.8 after OAR (P=.1020). Total complication rates were 20% after EVAR and 52% after OAR (P=.0378), and all complications were mild or moderate. Mean intensive care unit times were 0.2 days+/-0.4 after EVAR and 1.1 days+/-0.4 after OAR (P<.0001) and mean lengths of hospital stay were 2.3 days+/-1.0 after EVAR and 5.0 days+/-2.1 after OAR (P<.0001). Cumulative rates of long-term patient survival did not differ between EVAR and OAR (P=.144). No AAA-related deaths or aortoiliac ruptures occurred during follow-up for EVAR and OAR. In addition, no surgical conversions were necessary in EVAR recipients. Cumulative rates of freedom from secondary procedures were not significantly different between the EVAR and OAR groups (P=.418). Within a multivariable Cox proportional-hazards analysis adjusted for patient age, maximum AAA diameter, and cardiac risk score, all-cause mortality rates (odds ratio [OR], 0.125; 95% CI, 0.010-1.493; P=.100) and need for secondary procedures (OR, 5.014; 95% CI, 0.325-77.410; P=.537) were not different between EVAR and OAR. CONCLUSIONS: Results from this observational study indicate that EVAR offers a favorable alternative to OAR in young patients at low risk.

Performance characteristics and design recommendations for biomass-burning stoves using earthen construction materials

This report provides an analysis of the thermal performance and emissions characteristics of improved biomass stoves constructed using earthen materials. Commonly referred to as mud stoves, this type of improved stove incorporates high clay content soil with an organic binder in the construction of its combustion chamber and body. When large quantities of the mud material are used to construct the stove body, the stove does not offer significant improvements in fuel economy or air quality relative to traditional open fire cooking. This is partly because a significant amount of heat is absorbed by the mass of the stove reducing combustion efficiency and heat transfer to the cook pot. An analysis of the thermal and mechanical properties of stove materials was also performed. A material mixture containing a one‐to‐one ratio by volume of high content clay soil and straw was found to have thermal properties comparable to fired ceramics used in more advanced improved stove designs. Feedback from mud stove users in Mauritania and Mali, West Africa was also collected during implementation. Suggestions for stove design improvements were developed based on this information and the data collected in the performance, emissions, and material properties analysis. Design suggestions include reducing stove height to accommodate user cooking preferences and limiting overall stove mass to reduce heat loss to the stove body.